The body burden

By Michelle Chen Jun 09, 2009

Pollution is all around us, but the toll it takes on our bodies is often invisible. To understand the physical legacy of environmental toxins, dirty air and chemical products, environmental justice activists as well as federal agencies have begun to use “biomonitoring" to assess the “body burden” of various pollutants in human tissues. These studies yield critical data on the intersection between demographics and public health, but the science is still riddled with gaps. Organizations like the New York-based WE ACT, Citizens for Environmental Justice in Texas, and the Environmental Working Group, have raised awareness about the vulnerability of women and youth to various environmental hazards, including everyday exposure to air pollution and plastic chemicals. The Columbia Center for Children’s Environmental Health has partnered with WE ACT in a large long-term study of Black and Latino pregnant women in Uptown Manhattan and the South Bronx revealed public health threats peculiar to urban communities of color:

Children living in these vulnerable communities bear the unequal burden of poor health outcomes such as high rates of asthma, growth and developmental delays. Over the past ten years, this study has shown that exposure beginning in the womb to polycyclic aromatic hydrocarbons (PAHs) from traffic-related air pollution, pesticides in common home pest control products, and pest allergens in the home can result in asthma and other respiratory symptoms, delays in cognitive development, and changes at the molecular level that could increase children’s cancer risk.

So far, however, biomonitoring efforts have been piecemeal. The Government Accountability Office called out the Environmental Protection Agency for failing to develop a strategy to use biomonitoring as an instrument for developing new policies and holding polluters accountable.

For most of the chemicals studied under current biomonitoring programs, more data on chemical effects are needed to understand if the levels measured in people pose a health concern, but EPA’s ability to require chemical companies to develop such data is limited. Thus, the agency has made few changes to its chemical risk assessments or safeguards in response to the recent increase in available biomonitoring data. While EPA has initiated several research programs to make biomonitoring more useful to its risk assessment process, it has not developed a comprehensive strategy for this research that takes into account its own research efforts and those of the multiple federal agencies and other organizations involved in biomonitoring research.

The weak connection between environmental authorities and at-risk populations underscores the community engagement aspect of biomonitoring. In recent years, communities of color have seized on participatory research as a platform for empowering residents and informing policy. In the journal Race, Poverty and the Environment, Oakland-based Urban Habitat outlined the benefits of community-driven research. But the organization also noted the limitations of biomonitoring as an advocacy tool.

Biomonitoring identifies exposures that have already occurred. For example, many childhood lead poisoning prevention programs rely on testing children’s blood to identify children at risk. The problem with this approach is that it is an “after the fact” approach—by the time lead has reached levels of concern in the blood of children, damage may have already been done, and may be irreversible. This approach also essentially casts children as human lead detectors. More “upstream” approaches to lead poisoning prevention are now requiring mitigation of lead hazards in the home environment without relying on blood lead levels… Biomonitoring may focus community attention on a single problem, diverting it from other related social and environment factors that affect health. Ill health is a product of environments where exposure to toxins occurs alongside other social and economic hazards. The relationships among a range of adverse conditions and human health is best considered comprehensively.

While biomonitoring fills a limited niche in the environmental justice movement, it can empower grassroots organizations with hard data (which polluting industries can also wield to push their own agendas). If the new administration follows through on its commitment to science in the public interest, environmental health advocates could see new opportunities to take research out of the academy and into people’s neighborhoods.